The Robot Whisperer: Projects

#include <SPI.h>
#include <MFRC522.h>

#define SS_PIN  5    // the reader's SDA pin
#define RST_PIN 22

MFRC522 rfid(SS_PIN, RST_PIN);

void setup() {
    Serial.begin(115200);
    SPI.begin();       // SCK=18, MISO=19, MOSI=23 — ESP32 defaults
    rfid.PCD_Init();
    Serial.println("Tap a card...");
}

void loop() {
    if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) return;

    Serial.print("Card UID:");
    for (byte i = 0; i < rfid.uid.size; i++) {
        Serial.printf(" %02X", rfid.uid.uidByte[i]);   // hex! (see the Interlude)
    }
    Serial.println();
    rfid.PICC_HaltA();   // stop talking to this card
}

#include <SPI.h>
#include <MFRC522.h>
#include <ESP32Servo.h>

MFRC522 rfid(5, 22);
Servo bolt;
const int BUZZER = 15;

// The allow-list: UIDs you copied from the enrol sketch.
byte allowed[][4] = {
    {0x9C, 0x7A, 0x12, 0x4B},   // JB's card
    {0x04, 0xD1, 0x33, 0xA2},   // spare card
};

bool isAllowed(byte* uid, byte size) {
    for (auto& card : allowed) {
        if (size == 4 && memcmp(uid, card, 4) == 0) return true;
    }
    return false;
}

void setup() {
    Serial.begin(115200);
    SPI.begin();
    rfid.PCD_Init();
    bolt.attach(13);
    bolt.write(0);                 // start LOCKED
    pinMode(BUZZER, OUTPUT);
}

void loop() {
    if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) return;

    if (isAllowed(rfid.uid.uidByte, rfid.uid.size)) {
        digitalWrite(BUZZER, HIGH); delay(80); digitalWrite(BUZZER, LOW);
        bolt.write(90);            // open
        delay(3000);               // (make this non-blocking — Module 7!)
        bolt.write(0);             // auto-lock
    } else {
        for (int i = 0; i < 3; i++) {          // three angry beeps
            digitalWrite(BUZZER, HIGH); delay(60);
            digitalWrite(BUZZER, LOW);  delay(60);
        }
    }
    rfid.PICC_HaltA();
}

#include <Adafruit_NeoPixel.h>

const int PIN   = 16;
const int COUNT = 60;
Adafruit_NeoPixel strip(COUNT, PIN, NEO_GRB + NEO_KHZ800);

void setup() {
    strip.begin();
    strip.setBrightness(80);   // 0-255. Start LOW — full white is blinding
    strip.show();              // everything off
}

void loop() {
    // A moving dot ("chase") in your brand colour.
    for (int i = 0; i < COUNT; i++) {
        strip.clear();
        strip.setPixelColor(i, strip.Color(0x22, 0xD3, 0xEE));  // hex RGB —
        strip.show();                                           // the Interlude pays off
        delay(30);
    }
}

#include <WiFi.h>
#include "time.h"

void setup() {
    // ...connect Wi-Fi (Module 8)...
    // Ask an internet time server what time it is. UTC+3 = Kampala.
    configTime(3 * 3600, 0, "pool.ntp.org");
}

bool signShouldBeOn() {
    struct tm now;
    if (!getLocalTime(&now)) return true;    // clock not synced yet? stay on
    int minutes = now.tm_hour * 60 + now.tm_min;
    return minutes >= 18 * 60 + 30           // on from 18:30...
        && minutes <  23 * 60;               // ...off at 23:00
}

void loop() {
    if (signShouldBeOn()) {
        runAnimation();          // your chase/fade/scroll effect
    } else {
        strip.clear();
        strip.show();            // dark — saves power and bulb life
    }
}

#include <IRremote.hpp>

const int IR_PIN = 35;

void setup() {
    Serial.begin(115200);
    IrReceiver.begin(IR_PIN);
    Serial.println("Point any remote at the eye and press buttons...");
}

void loop() {
    if (IrReceiver.decode()) {
        // Every button sends its own code. Write them down.
        Serial.printf("code: 0x%02X\n", IrReceiver.decodedIRData.command);
        IrReceiver.resume();     // ready for the next press
    }
}

#include <WiFi.h>
#include <WebServer.h>
#include <IRremote.hpp>

const int RELAY = 26;
WebServer server(80);
bool lightOn = false;

void setLight(bool on) {
    lightOn = on;
    digitalWrite(RELAY, on ? HIGH : LOW);   // HIGH = relay clicks closed
}

void setup() {
    pinMode(RELAY, OUTPUT);
    // ...connect Wi-Fi (Module 8)...
    IrReceiver.begin(35);

    // Three tiny HTTP endpoints — your phone/app is the remote now.
    server.on("/on",  [] { setLight(true);  server.send(200, "text/plain", "ON");  });
    server.on("/off", [] { setLight(false); server.send(200, "text/plain", "OFF"); });
    server.on("/toggle", [] {
        setLight(!lightOn);
        server.send(200, "text/plain", lightOn ? "ON" : "OFF");
    });
    server.begin();
}

void loop() {
    server.handleClient();                   // app control
    if (IrReceiver.decode()) {               // remote control
        if (IrReceiver.decodedIRData.command == 0x45) {   // your power button
            setLight(!lightOn);
        }
        IrReceiver.resume();
    }
}

#include "esp_camera.h"

void setup() {
    Serial.begin(115200);

    camera_config_t cfg = {};
    cfg.pixel_format = PIXFORMAT_JPEG;
    cfg.frame_size   = FRAMESIZE_SVGA;   // 800x600 — good speed/size balance
    cfg.jpeg_quality = 12;               // lower number = better quality
    cfg.fb_count     = 1;
    // ...plus ~16 pin assignments for the AI-Thinker board.
    // Copy that block verbatim from the CameraWebServer example —
    // every ESP32-CAM project uses the exact same lines.

    if (esp_camera_init(&cfg) != ESP_OK) {
        Serial.println("Camera init failed");
        return;
    }

    camera_fb_t* fb = esp_camera_fb_get();      // take one photo
    Serial.printf("Captured %u bytes of JPEG\n", fb->len);
    esp_camera_fb_return(fb);                   // ALWAYS hand the buffer back
}

void loop() {}

#include <HTTPClient.h>

// Send a captured frame to your own backend (the Go server from Module 11).
void sendPhoto(camera_fb_t* fb) {
    HTTPClient http;
    http.begin("http://your-server.com/api/doorbell");
    http.addHeader("Content-Type", "image/jpeg");
    int code = http.POST(fb->buf, fb->len);     // raw JPEG bytes, no base64
    Serial.printf("Upload: HTTP %d\n", code);
    http.end();
}